Subtract 40/45 from 70/80
70/80 - 40/45 is -1/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
70/80 = 70 × 9/80 × 9 = 630/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
40/45 = 40 × 16/45 × 16 = 640/720 - Subtract the two like fractions:
630/720 - 640/720 = 630 - 640/720 = -10/720 - After reducing the fraction, the answer is -1/72
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